Despite improved rational drug design and a remarkable progress in genomic, proteomic and high-throughput screening methods, the number of novel, single-target drugs fell much behind expectations during the past decade. The project is aimed to find novel drug targets, which are less vulnerable to the development of resistance, and to the mobilization of secondary pathways of cellular networks. As a part of this effort, design strategies to find appropriate target-sets of multi-target drugs are to be developed using multiple perturbations of protein-protein interaction networks.